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cremeglace writes "In the late 1990s, astronomers noticed a distinct warp in the disk of dust and gas orbiting a young star some 60 light-years from Earth. Now, using new analytical tools, researchers have discovered a giant planet lurking within the dusty haze. About nine times as massive as Jupiter and composed mainly of gas, the planet is only a few million years old, proving that such enormous planetary bodies can form rapidly."
What's amazing about this is that the images taken of the star clearly show the planet first on one side of the star, and then the other, several years later.

Ok, IANAA (*not an astronomer) but what's amazing about the planet on one side of the star and then the other several years later? Don't most planets orbit stars at varying rates ("years" to us earthlings)? I'm confused by the fact that it's amazing for a large planet to be orbiting its star.

Ok, decades to orbit, at a distance of between 8 to 15 Astronomical Units, so in this case TFA says an orbital period between 17 and 35 years.

Also it was mentioned that it was only a few million years old, like they had tree rings or something. They just found it, they are still amazed they can see it, yet they already have its age determined?

What's amazing isn't that the planet is orbiting it's parent star, it's the technology to take a picture of the planet and be able to see it moving over time. Most extrasolar planets aren't detected this way, they usually use either Doppler shift or reduction in brightness to detect the existence of a planet and extrapolate from there. There's only a handful of examples of optically sighted extrasolar planets, and this is the first I've heard of having two pictures of the same system, both with the planet visible.

Not only is that 'cool' but it allows us to start cataloging planets that orbit their stars on a plane perpendicular to the direction we are viewing them. Previously, a planet had to conveniently be orbiting such that we were looking into the system edge on. The real excitement will come when we can view terrestrial planets this way with enough resolution to perform spectrographic analysis on the atmosphere and search for, among other things, sings of life.

FWIW, mass isn't the story here; we know of hundreds of planets in that mass range. I would say the story is that two images taken a few years apart show the planet's motion, and that Beta Pic, the parent star, was the first to have a disk seen around it back in the 1980s. This planet explains the warp and other features in the disk, too, that have been known for years! I wrote about this on my Bad Astronomy blog [discovermagazine.com].

You could have an object the size of our solar system, with a very low density, but a mass that far exceeds our sun, which would just remain a non-burning object.

If the density reaches a critical threshold, it could then start burning, and be a star. Well, if the density becomes too great, it could also become a black hole (i.e., extreme gravitational force, pulling everything including light b

Gravity makes things denser if you just add mass. If you want stuff to be less dense, you have to heat them up, probably by starting fusion in the core. Just adding more mass to Jupiter won't change the volume significantly, it just gets compressed.If you start fusing Helium instead of Hydrogen in the core, temperatures there rise dramatically, allowing the outer, non-fusing parts of the object to expand.

I remember reading that too. I think you're right about the density... Jupiter's diameter should be about as large as gas giants get... any more material falling in would simply compress the core more and make it denser. If Jupiter were about 10 times more massive, however, it'd ignite and turn into a small star... so this planet might still be just below that threshold. But maybe since it's so large and diffuse, it might be spinning much faster to counteract all that gravity...

If it shines it's a star.Else if the mass is greater than the theoretical minimum for fusion (13 Jupiter masses), it is a brown dwarf.Else if the mass orbits a star or stellar remnant it is a planetElse it is a 'sub-brown dwarf'

Why make up “theoretical”-based definitions?And why the pointless dichotomies?

If it does fusion (no matter the size), it’s at least a brown dwarf, but a better name (star-like) would make more sense.The more it shines, the more of a star it is.Else if it orbits something it’s a planet. (That’s what the word means, after all.)If it doesn’t, it’s something that we don’t have a name for yet, but that we may also call a planet nowadays.No that does not mean that t

The universe is a pretty big place, or so I have been told. Undoubtedly if you look long enough you will find entities that challenge your preconceived label or definition of what something "IS". In a universal sense, everything is in flux, so all we are really doing is classification of temporal slices that we can deal with in our limited capacity. At exactly what point does a X become a Y? Considering the time frame being measured is so long, and our perspective so short, it becomes a point of debate, depending on what you call one thing in terms of the other.

Are you so sure about that? Wouldn't it be more efficient to find a planet that will be moving close to your destination with a few viable life forms, let them propagate, and then collect them later? The Earth is like a nice petri dish. Drop a few specimens in, and in a while you have a full fledged colony.

We'll find out in about 2 years, when we've come to our destination, and the planet is culled for the slaves that have been propagating across it.

Are you so sure about that? Wouldn't it be more efficient to find a planet that will be moving close to your destination with a few viable life forms, let them propagate, and then collect them later? The Earth is like a nice petri dish. Drop a few specimens in, and in a while you have a full fledged colony.

What? We were made so aliens can use us as slaves? RAEL LIED TO ME!

(Actually, despite the random chatter I've heard from Raelians, I don't recall hearing something to specifically disprove this theory. Not that I really listened.)

Considering how loudly we broadcast to the universe, we probably create a much bigger foot print in the RF than a planet our size should. So, they might find us eventually. Whether or not we want to be found is a different question, and I think the answer lies in the benevolence of our discoverers. But if there's intelligent life within only 60 l.y., then we've probably been heard or will be soon enough.

This mass of this gas giant still isn't enough to get anywhere near minimum star size. Gas giants need to be ~8 times as massive as this porker to even get into the brown dwarf range. Quite amazing when you think about it.